1. Field of the Invention
The present invention relates to a bicycle and, in particular, to an easy-pedaling and labor-saving bicycle.
2. Description of the Related Art
Referring to FIG. 1, a conventional bicycle 1 comprises a frame 11, a front wheel 12 and a rear wheel respectively pivoted on the frame 11, and a pedal device 14 driving the rear wheel 13. The pedal device 14 includes a front sprocket 141, two supporting arms 142 respectively pivotally disposed on the frame 11 for activating the front sprocket 141, a plurality of pedals 143 respectively connected to the front sprocket 141, a rear sprocket 144 connected to the rear wheel 13 for unidirectionally driving a rotation of the rear wheel 13, and a chain 145 disposed between the front sprocket 141 and the rear sprocket 144. When a user rides the conventional bicycle 1, the pedals 143 are rotated in circumference to allow the front sprocket 141, the chain 145 and the rear sprocket 144 to be sequentially activated for driving a rotation of the rear wheel 13 and giving the bicycle 1 a forward momentum. However, the length of the supporting arms 142 is too short, which limits the generation of the force moment and consumes labor.